2001 Pathfinder SE 2WD A/T: TCM issue (Code: P1605)

[Nola_R50]

Hey yall,

So today I was driving my PF and everything was fine, ran a few errands with no issues. I stopped at Lowes, and when I was leaving i noticed the transmission was acting weird. I felt like I was taking off in a higher gear, RPMs were around 2k, and the downshifts were rough. It almost felt like it was constantly slipping while taking off from a stop. I got home and checked the fluid first. It was at the proper level, perfect color, no glitter and no burnt smell. After that I ran the codes to find the P1605 "A/T control unit or circuit fault". Looked on a forum and someone with the same symptoms on their 01 said replacing their TCM was the fix.

I went to the junkyard and snagged one out of an 02, and got back home to take mine out. But i noticed that mine is 4W000, while the donor truck's is 4W002.

So my question is: Will the 4W002 work for my 01 that originally had the 4W000? Or will I fry something inside of the transmission if I try running it?

Thanks in advance!

[Nola_R50]

UPDATE: I replaced the module (battery was disconnected) and I now have a no start no crank, along with 5 new codes. Codes make no sense either (o2 sensors, camshaft position sensor, and of course the P1605. Battery voltage is at 12 and all of my lights come on. I'm starting to think that maybe my ecm is the culprit?

I replaced my IACV last year because I was having some idlling issues. Is it possible the new one has failed and fried the ecm like I've heard from other owners?

[VStar650CL]

I don't think there's any way to tell that. To my knowledge Nissan doesn't sell those TCM's separate from the Valve Body, so the TCM part number would only mean anything to the manufacturer of the VB. However, the parts catalog only shows one VB from 01/2000~07/2001 and another from 08/2001 up, so I'm pretty sure if you got it from a truck with a production date that corresponds with yours, there shouldn't be an issue.

[Nola_R50]

I think the truck I got it off was between the 01/200-07/2001 period. I grabbed another from an 03 and the part number on the module was completely different, so I left that one behind.

But now I'm pretty sure its not my TCM, as I'm having a no crank no start. Cleaned all of my battery connections and battery tested good, so I'm going to try testing the ECM and Park/Neutral relays next.

Thank you for the response!

[VStar650CL]

Check the TCM fuse before anything else. I'm not sure on an '01 whether the TCM sends the P/N signal on CAN or drives the relay directly, but it will be one or the other. So a dead TCM will cause a no-crank every time.